Hearing aid using T4 and audio shield

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I'm using the T4 dual ADC in sync mode to capture both channels in 6.3 usec(167Ks/s). Adding two 3-pole HP Bessel filters sequentially adds only 0.4 usec. There will be some software mixing of the input audio and the filter output to enhance the high freqs but that should be trivial. There's also some Serial.print statements in the loop now that will be removed or made active when a monitor is connected. The loop is timed to repeat every 50 usec so there's plenty of time to do the DAC output as long as they're not I2C based. I looked at the audio shield and tutorial but find it quite intimidating as to what goes into the setup() and loop() routines. That option is still open as the Adafruit board and no T4 compatible library is a 'no' at this point. All I really need now is a fast DAC output.
 
YOu dont need that samplerate - and even if you needed it, there's the PCM1808(ADC) / PCM5102 (DAC) for example - I'm using them for 256kHz samplerate. Great Audio quality.
There are no limits. You can use your own queues or create new audio objects, filters, etc..

... you don't want the audio lib, don't want proven solutions, and want to go your own way - which ist totally OK. - But I can't help there and I'm out now.

My best wishes, stay healthy,
Frank.
 
At this point, I've not made a decision either way. I'll look into the audio tutorial some more and if I feel comfortable enough with the programming then I'll go that route.

Thank you for all of your replies and info, it's appreciated.
Ed
 
At this point, I've not made a decision either way. I'll look into the audio tutorial some more and if I feel comfortable enough with the programming then I'll go that route.

Thank you for all of your replies and info, it's appreciated.
Ed

Your might want to look at the queues (Record+play queue) - With the help of these you can add your own code easily. If you want higher SampleFrequency than 44.100Hz (but really - you don't need this), ask me.
 
I'm working on a sonar project at the moment but will be back on the hearing aid shortly. It will not use the shield but instead have an MCP4922 chip for the dual channel DAC. That chip interfaces directly to the T4.0 via SPI. I can write a data pair to it at over 400Kdpps but need only 40Kdpps now. This will reduce the part count and size of the main unit.
 
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